The present invention relates to a data cartridge holder that is capable of accommodating a plurality of data cartridges.
Data cartridge holders are box-like structures that are used to retain one or more data cartridges in a preferred orientation. For example, data cartridge holders are integral parts of tape libraries that store a plurality of tape cartridges. To elaborate, the typical tape library includes one or more tape cartridge holders for accommodating a plurality of tape cartridges, a player/recorder for reading/writing data from/on a recording tape located within a tape cartridge, and a picker assembly for moving tape cartridges between the tape cartridge holders and the player/recorder. In tape libraries, the typical tape cartridge holder is used to place the tape cartridges in preferred orientation that facilitates the operation of the picker assembly. For example, one or more tape cartridge holders can be used to position tape cartridges in a one-dimensional vertical array, a two-dimensional x-y array or a curved array.
Data cartridge holders that are capable of accommodating a plurality of data cartridges typically include an open-sided box-like structure with partitioning elements that divide the interior space of the box-like structure up into a plurality of slots that are each capable of accommodating a data cartridge. In many cases, it is also desirable to prevent the accidental or unintentional dislodgement of a data cartridge that is being stored in such a holder. For example, if a tape cartridge were to fall out of a slot in a tape cartridge holder in a tape library, the dislodged tape could disrupt the operation of the picker assembly. Consequently, many data cartridge holders employ a retaining structure that prevents an unintentional dislodgement of a data cartridge but permits a desired extraction of the data cartridge from the holder.
Also part of many data cartridge holders are orientation structures that inhibit the insertion of a data cartridge into the holder if the cartridge is incorrectly oriented. The orientation of a data cartridge is important in many situations. For example, in tape libraries, the tape cartridges must be properly oriented in the tape cartridge holders so that when the picker assembly is moving a tape cartridge from the holder to the player/recorder, the picker does not have to re-orient the tape cartridge for insertion into the player/recorder.
The present invention is directed to a data cartridge holder that is capable of accommodating a plurality of data cartridges and has a retaining structure that takes advantage of one or more features associated with the door of a cartridge. The 8 mm tape cartridge possesses several of the door related features that are utilized by the retaining structure of the present invention to retain a cartridge. To elaborate, an 8 mm tape cartridge has a housing that includes two lateral sides that are substantially parallel to one another, a front side and back side that are also substantially parallel to one another, and top and bottom sides that are substantially parallel to one another. A U-shaped door provides, when open, access to the tape media located within the housing and when closed, protects the tape from being damaged. The U-shaped door includes a pair of lateral sides that are pivotally connected to and form part of the lateral sides of the housing. A front face of the door connects the lateral sides of the door to one another and forms the front side of the housing. The lateral sides of the housing each include a gripper notch that is used by a picker assembly to insert/retract a data cartridge. Further, the lateral sides of the door each include a small hole, sometimes known as a light path window, that is used by a player/recorder to determine when the door is open and closed. Between one of the lateral sides of the door and the remainder of the housing is a discontinuity. Characteristic of this discontinuity is that the outer edge of the door forms part of the discontinuity and that the discontinuity changes in shape when the door is moved between the open and closed positions.
The retaining structure of the data cartridge holder makes use of the discontinuity associated with the door to prevent the accidental or unintentional removal of the cartridge from the holder. By using the discontinuity associated with the door rather than the gripper notches or light path windows to retain a data cartridge, a number of problems are avoided. For instance, a retaining structure that makes use of the gripper notches to retain a data cartridge in a holder can interfere with the operation of the picker mechanism during insertion/extraction operations. Similarly, a retaining structure that uses the light path windows can potentially damage the windows and thereby inhibit the function for which they were designed, i.e. for the detection of whether the door is open or closed.
One embodiment of the retaining structure of the data cartridge holder includes a cantilever member with a first end that is fixed to a wall of the cartridge holder a second end that engages the particular door feature that is being exploited to retain the data cartridge and is capable of flexing in response to, for example, the insertion/retraction of a data cartridge by the picker. In a particular embodiment that facilitates manufacture of the holder, the first or fixed end of the cantilever is located directly below the second or free end of the cantilever member. With this orientation, the fixed end of the cantilever member is located closer to the bottom wall of the holder and the free end of the cantilever member is located closer to the open side of the holder, i.e. the side through which the data cartridges and inserted and retracted.
Also provided by the present invention is a data cartridge holder with an orientation structure that is used to inhibit the complete insertion of an incorrectly oriented 8 mm tape cartridge into the holder. To elaborate, analysis of the 8 mm tape cartridge revealed a ramp that extends between the front and top faces of the cartridge, which is essentially one of the four longitudinal comers of the cartridge housing. None of the other longitudinal comers of the housing have such a ramp. Stated differently, the ramp is an asymmetry. The data cartridge holder exploits this asymmetry to prevent the complete insertion of an incorrectly oriented data cartridge into the holder. In one embodiment, a structure that is complementary to the shape of the ramp is established at each end of a slot. The structure operates to permit the complete insertion of a correctly oriented cartridge. However, the structure inhibits the complete insertion of an incorrectly oriented cartridge. Characteristic of an incorrectly oriented data cartridge is that one of the other longitudinal comers will come into contact with the orientation structure. Since none of these other longitudinal comers have a ramp that is complementary to the orientation structure, the structure will interfere or prevent the cartridge from being completely inserted into the holder.
In yet another embodiment, a data cartridge holder is provided that can be inserted into and removed from a tape library. The holder includes an open-side box-like structure for holding the cartridges, a dust cover and a coupling apparatus for attaching the dust cover to the holder when the holder is in use, i.e. mounted in a tape library such that cartridges can be inserted into and removed from the holder. When the holder is not in use, i.e. not operably positioned within a tape library, the dust cover can be placed over the opening of the box-like structure to protect any data cartridges housed within. In one embodiment, the dust cover has a U-shaped cross section and the coupling apparatus serves to connect the dust cover to the box-like structure such that the box-like structure is nested in side the U-shaped dust cover. A further embodiment of the holder includes a connector for use in attaching/detaching the holder from/to a library. Also part of such a connector is a reference device that is used to assure the proper orientation of the holder within a library.